Method for preparing polyhydroxy-aromatic compounds rich in meta orientation



United States Patent "ice 3,440,296 METHOD FOR PREPARING POLYHYDROXY AROMATI'C COMPOUNDS IN META ORIENTATION Alexander H. Widiger, Jr., Midland, Mich., assignor to 3,440,290 Patented Apr. 22, 1969 hydro. quinone; N-2 repre ents. the is( ydroxyp ny ethers aving the generic, formula The Dow Chemical Company, Midland, Mich., a cor- 5 poration of Delaware No Drawing. Filed Aug. 5 1965 Ser. No. 477 610 Int. Cl. C07c 37/00, 39/i28,43/22 l as the mhydroxy dlphqnyls gene US. Cl. 266-613 9 Claims fmmfla The present invention relates to an improved method 10 for preparing resorcinol, catechol, dihydroxy diphenyl HO OH ethers trihydroxydiphenyls and highers in commercially economical quantities employing milder react-ion condi- OH tions, I .1 actantnore economical reactants and easier to handle re and represents the bls (11y dmxyphmoxy )benzenes,

There is much prior art in the field of hydrolyzing chlorobenzenes, dichlorobenzenes and chlorophenols. It is, however, believed that none of the prior workers recog- HO O O OH nized the significance of the strength of the caustic on the overall yield of valuable products.

The present process comprises reacting about one mole th h d h dih d h 1 of a chlorophenol or a mixture of the isomers thereof with e y foxy P enoxy y roxy 1P any S from 4 to 8 moles, and preferably 5 to 6 moles, of sodium hydroxide as a 20 to 50% aqueous solution under the HO O (0E2 autogenous pressure of the mixture at about 250 to 270 C., and preferably at about 265 C. for from about /2 to about 2 hours. The resulting products, rich in meta and some tetrahydroxy triphenyls (6%), orientation, are principally dihydroxy benzenes and d1- droxy diphenyl ethers. The products can conveniently be I separated from the reaction mixture by acidification there- -(OH)4 of to a pH value of about 3 to about 6 and subsequent ex- J traction with an organic extractant, such as sec. butyl alco hol, amyl alcohol, and the like, and recovered from the The following examples illustrate the process of the extractant and from each other by fractional distillation present invention but are not to be construed as limiting. under vacuum.

The process of the present invention can be carried EXAMPLES out to yield about 60% conversion, :based on the chloro- A series of experiments were run to Iestabhsh the limits phenol consumed, at 65 C., Within 30 minutes when reactants of the present process. Eac experiment conusing at least some ortho and/ or para isomer in the start- 40 sisted of the reaction at 265 C. of the indicated chloroin chlorophenol. Longer reaction periods do not rnaphenol isomer with c.p. sodium hydroxide and distilled tei ially increase the yield of desired products, that is, the water. The reaction was carried out in an iron bomb dihydroxy benzenes and the dihydroxy diphenyl ethers placed in a rocker. The reaction time was 30 minutes for but longer periods are not materially detrimental to the the ortho and meta isomers and 120 minutes for the para 511 523333722? 5 035 1251322.3335?ald ii irilifiiii iii iv tfiiiiii tifiiiiifiif1?filiiiiii slightly greater than autogenous pressures the time will ucts were separated from the aqueous phase :by 4 extracvary approximately inversely to the temperature. tions with sec. butyl alcohol. The alcohol was removed In the following examples the products are defined as from the extracted organic phase by distillation under N-l, N2, and N-3. These symbols represent the number vacuum and the products separated one from the other by of phenylene nuclei in the compounds. Thus, N-l represents the dihydroxy benzenes, catechol, resorcinol and fractional distillation in vacuo. The results of the series of runs are set out in the tables below.

NaOH Product grams Percent Percent Dist. dihydroxy compounds in N-l Chloro- Grams Strength, phenol, g. ClOH N-l N-2" N-3 Conv. Yield 0 M P percent on'rno META PAR

*These symbols have the significance aforesaid.

2 Balance if any para.

9 Balance if any ortho.

1 Two replicates of this experiment were run and the data is that ob- Three replicates.

tained by combining the two products recovered on removal of the sec. butyl alcohol.

I claim: 1. A method for preparing a polyhydroxy aromatic product which comprises reacting a mixture consisting essentially of a chlorophenol with from 4 to 8 moles of 20 to 50% aqueous solution of sodium hydroxide under the mixtures autogenous pressure at a temperature of from about 250 to 270? C. for between about /2 to 2 hours, and separating from the reaction mixture a product rich in meta oriented dihydroxybenzene, dihydroxy diphenyl ethers and trihydroxy diphenyl, and low in hydroxy phenoxy phenoxyphenols, and highers.

2. The method of claim 1 wherein the chlorophenol is meta chlorophenol.

3. The method of claim 1 wherein the chlorophenol is ortho chlorophenol.

4. The method of claim 1 wherein the chlorophenol is para chlorophenol.

5. The method of claim 2 wherein the reaction temperature of'265" C.

6. The method of claim 5 wherein the reaction period is about' /z hour.

7. The method of claim 4 wherein said reaction temperature is 265 C. and the reaction period is 120 minutes.

8. The method of claim 3 wherein said reaction temperature is 265 C. and the reaction time is 6 hour.

9. The method of claim 1 which consists essentially of reacting a chlorophenol with 5 to 6 moles of 20 to 50% aqueous solution of sodium hydroxide at about 265 C. for /2 to 2 hours.

References Cited UNITED STATES PATENTS 2,041,592 5/1936 Burroughs 260-629 BERNARD HELFIN, Primary Examiner.

U.s.' c1. X.R.

U.S. DEPARTMENT OF COMMERCE PATENT OFFICE Washington, 0.6. 20231 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 ,440 ,290 April 22 1969 Alexander H. Widiger, Jr.

It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 38, "65 C." should read 265 C. Columns 1 and 2, in the table, second column, line 14 thereof,

"26.5" should read 62.5

Signed and sealed this 14th day of April 1970.

(SEAL) Attest:

Edward M. Fletcher, J r.

Attesting Officer Commissioner of Patents WILLIAM E. SCHUYLER, JR. 

1. A METHOD FOR PREPARING A POLYHYDROXY AROMATIC PRODUCT WHICH COMPRISES REACTING A MIXTURE CONSISTING ESSENTIALLY OF A CHLOROPHENOL WITH FROM 4 TO 8 MOLES OF 20 TO 50% AQUEOUS SOLUTION OF SODIUM HYDROXIDE UNDER THE MIXTURES AUTOGENOUS PRESSURE AT A TEMPERATURE OF FROM ABOUT 250* TO 270*C. FOR BETWEEN ABOUT 1/2 TO 2 HOURS, AND SEPARATING FROM THE REACTION MIXTURE A PRODUCT RICH IN META ORIENTED DIHYDROXYBENZENE, DIHYDROXY DIPHENYL ETHERS AND TRIHYDROXY DIPHENYL, AND LOW IN HYDROXY PHENOXY PHENOXYPHENOLS, AND HIGHERS. 